A new Personal Exposure Analyzer (PEA) has been developed with NIH funding by X-Ray Optical Systems (XOS), East Greenbush, New York, and is based on a novel, non-destructive spectroscopic technique called energy dispersive (ED) monochromatic micro-X-ray fluorescence (M5XRF). This novel analyzer is designed to be used in the field by non-laboratory trained staff to assess human exposure to multiple metals in a variety of sample types (e.g., cosmetics, personal hygiene products) and matrices (e.g., liquid to solid) that an individual is exposed to or comes into contact with in a variety of environmental contexts (e.g., home or workplace). This includes samples of liquids we consume (water, juice, tea, wine, salad dressings, and other condiments, etc.); lotions and gels that are applied to the body (makeup, perfume, sun block, antiperspirant, shampoo, soap, toothpaste, and other personal hygiene products, etc.); as well as samples of food or ingestible material (spices, nuts, dietary supplements, pills, etc.) that can be easily crushed, powdered, or homogenized. The primary goal of this project is to validate exposure measurements obtained with this new analyzer under field conditions by deploying it in an on-going biomonitoring study of mercury exposure in subjects of ethnic Chinese background living in the Capital Region (Albany- Schenectady-Troy) of New York State, funded by a CDC award to New York State. Between 25 and 30 personal environmental samples will be collected during scheduled home visits to participants, along with biological samples (urine, blood), and analyzed for metal content (including mercury). The samples analyzed on site with the PEA will also be analyzed for metal content in a reference laboratory using gold standard methods of analysis. Results from the XRF (non-destructive) analyzer and the high-cost, gold standard laboratory-based methods (destructive) will be compared to the PEA results as part of the validation process. The validity, ease of use and ruggedness of the analyzer will be assessed under field conditions and the data used to assess it potential for use in other epidemiological studies. This project builds on an existing collaborative relationship between scientific and engineering staff from XOS, and environmental analytical scientists from the New York State Department of Health's Wadsworth Center. The research team also builds on a growing collaborative relationship between Wadsworth Center scientists and environmental epidemiologists working with the NYS DOH's Center for Environmental Health, in Troy New York.